Техническое чтение для энергетиков. Бухарова Г.П. - 83 стр.

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85
last century, when electricity was still a mysterious and alarming novelty. The
engineers who built London's first power station, with a 10,000-volt generator, in
1889, and their German colleagues who set up a 16,000-volt dynamo driven by a
waterfall in the River Neckar, to supply Frankfurt, 100 miles away, with electricity in
1891 – these men must have felt like true pioneers, derided, despised, and abused by
the diehards. There were, of course, also some powerful commercial interests in-
volved, for the gas industry feared for its monopoly in the realm of lighting– and with
a good deal of justification
as it turned out.
THE GREAT INVENTION OF JAMES WATT
By the middle of the 18th century, however, the childhood of the steam-engine
was already drawing to an end. A young Scotsman by the name of James Watt, the
fifth son of a ship's carpenter gave the machine its most efficient form – and thereby
helped to revolutionize the British way of life.
He was a weakly child, suffering from headaches and unable to go to school.
His mother taught him, and as soon as James could read he began to devour books.
At the age of 15 he had learnt most of what was then known about physics, and his
father sent him to Glasgow to study advanced mechanics. Later, his professor helped
him to set himself up as an instrument-maker and 'machine-doctor' in a shop in the
University building.
One day in 1763 –Watt was 27 years old –he was asked to repair a small model
of a Newcomen engine,which was needed for the natural-science lectures. The little
machine refused to work properly, stopping again and again after a few strokes of the
piston.
Watt examined it carefully. It had a boiler in which the steam was produced. At
the bottom of the cylinder were two valves, one to admit the steam and the other to
let a jet of cold water cool the cylinder when the piston had reached its highest point
This caused the steam to condense – and as steam takes up 1,700 times more space
than water a vacuum was created under the piston, and it was forced down by the
pressure of the atmosphere.
It was clear to Watt's inquisitive mind that this machine, even when in perfect
working order, used the steam not nearly efficiently enough. Was there, he asked
himself, sonic better way of making the piston move? The cold-jet injection seemed
too clumsy to him.
For two years he tried to find a solution to the problem. 'One Sunday afternoon
in 1765, he recalled later, 'I had gone for a walk and my thoughts turning naturally to
the experiments I had been engaged in for saving heat in the cylinder, the idea
occurred to me that, as steam was an elastic vapour, it would expand, and rush into a
previously exhausted space; and that if I were to produce a vacuum in a separate
vessel, and open a communication between this and the steam in the cylinder, such
would be the result.'
It was this idea of the separate condenser which made the steam-engine the first
great prime mover in modern times. Now the cylinder could remain hot, without

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